Population And Diversity Of Soil Microorganism In The South-north Hills In Lanzhou

On basis of the principles of soil microbiology , an experiment was conducted to compare the effects of five Arbores-bushes-grass in the south-north hills in Lanzhou on population, diversity and functional groups of soil microorganism. The main research results are as the follows:1.In this region,the amount of soil microbes was abundant as the follows .1) The sorting of soil microbes is: Lanshi Forest in the south hill(A)>Qidaoliang in the south hill (B) >Xujiashan mountain(C)>Lanhutai in north hill(D).2)The different proportions of fungi, bacteria and actinomycetes in a plot was obvious and in the order. Bacteria(×107)> actinomycetes (×105)>fungi(×104).2.Population of soil microbes was affected by the various Vegetation,Site type and Season to different extent as the follows.1) In five vegetations , Caragana korshinskii resulted in greater population of soil fungi and bacteria than he other four ; The actinomyces quantity in the soil of Hipp op hae rham noides were much larger than others with different bacteria and fungi.2) Total quantity of soil fungi, bacteria and actinomycetes of the south hill was consistently higher than the north hill.3)Total quantity of soil fungi, bacteria and actinomycetes in Autumn was higher than Spring.4) The quantity of soil fungi, bacteria and actinomycetes clearly decreased with the soil depth.3. Under conditions of this experiment, superiority community resulting from treatments of the various vegetation and the site type was the major factor for influencing on soil fungi, bacteria and actinomycetes composition.1)In treatment of the various vegetation, soil fungi community structure multiple Simpson (J) index, though not very obvious, could be ranged as Hipp op hae rham noides > matrimony-vine > Chinese tamarisk>Caragana korshinskii> Platy clad us orientalis.which involved with factors such as site type and soil depths. Shannon (H) index were remarkable affected by the various vegetation; Comparison the north hill with the south hill, soil fungi community structure multiple Simpson (J) index were the north hill > the south hill and Shannon (H) index were greatly affected by site type.2) Under conditions of this experiment, superiority community resulting from treatments of the various vegetation and the site type was the major factor for influencing on soil fungi composition. In treatment of the various vegetation, soil bacteria community structure multiple Simpson (J) index were not very obvious,Shannon (H) index were remarkable affected by the various vegetation; Comparison the north hill with the south hill, soil bacteria community structure multiple Simpson (J) index were remarkable affected and Shannon (H) index were not very obvious.3)Soil actinomycetes community structure multiple Simpson (J) index could be ranged as Hipp op hae rham noides > Platy clad us orientalis>mareimony -vine > Caragana korshinskii > Chinese tamarisk. which involved with factors such as site type and soil depths.4. The quantities of soil microorganism specified functional groups were significantly affected by the different the various vegetation and site type.1) There were apparent differences among the various vegetation in quantities of soil aerobic nitrogen-fixing bacteria, resulting in a range as Caragana korshinskii > Chinese tamarisk >Hipp op hae rham noides > Platy clad us orientalis > matrimony-vine ; Total quantity of soil soil aerobic nitrogen-fixing bacteria in the south hill was consistently higher than the north hill.2) The quantities of soil the aerobic cellulose-decomposing bacteria were not very obvious by the different the various vegetation; The quantities of soil aerobic cellulose decomposing bacteria showed significant differences in the 10-20 cm and 20-30cm soil layer of the south hill with the north hill.